Third International Workshop on "Geographical Analysis, Urban Modeling, Spatial Statistics"

1. Sampling Optimization Trade-offs for Long-term Monitoring of Gamma Dose Rates S.J. Melles, G.B.M. Heuvelink, C.J.W. Twenh ö fel, and U. St ö hlker Presented at ICCSA, GEOG-AN-MOD July 2, 2008, Perugia, Italy

5. Part 2: Methods to predict or describe spatial variability in environmental variables

10. Part 2: Example: γ - dose rate radiation

12. Spatially correlated residuals notice directionality in residuals 0 frequency 60 0 40 -40

13. Modelled with aniso variogram spherical and linear component in all directions, but spherical is dominant in swesterly and linear in ortho

14. Regression kriging prediction 30 80 nSv/hr

15. Kriging prediction error variance 65 85 nSv/hr

16. Part 3: Optimization

19. Minimizing the objective function (RKSE) Current design Optimized design

20. Examining the trade-offs? Costs

21. Part 4: What have we learned? Where to from here?

23. Doesn’t that look like even spatial coverage sampling? Current thinned design ( 50% stations) Optimized design (50% stations) Npp

26. THANK YOU!

27. Appendix

28. P of accepting a worsening design Delta f is the change in MUKV

31. Dynamic case